CreateSpace Independent Publishing Platform · Independently published
| title | ISBN-13 | year of publication |
|---|---|---|
| 2016 Geotechnical Business Directory | 978-1-5393-3063-9 | 2016 |
| 2017 Geotechnical Business Directory | 978-1-5488-1987-3 | 2017 |
| 2018 Geotechnical Business Directory | 978-1-7229-5554-0 | 2018 |
| 2019 Geotechnical Business Directory | 978-1-6919-3503-1 | 2019 |